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-rw-r--r--xlators/storage/posix/src/posix-handle.c621
1 files changed, 621 insertions, 0 deletions
diff --git a/xlators/storage/posix/src/posix-handle.c b/xlators/storage/posix/src/posix-handle.c
new file mode 100644
index 00000000000..b0693324d32
--- /dev/null
+++ b/xlators/storage/posix/src/posix-handle.c
@@ -0,0 +1,621 @@
+/*
+ Copyright (c) 2011 Gluster, Inc. <http://www.gluster.com>
+ This file is part of GlusterFS.
+
+ GlusterFS is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation; either version 3 of the License,
+ or (at your option) any later version.
+
+ GlusterFS is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see
+ <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <libgen.h>
+#include <alloca.h>
+
+#include "posix-handle.h"
+#include "posix.h"
+#include "xlator.h"
+
+
+#define HANDLE_PFX ".glusterfs"
+
+#define UUID0_STR "00000000-0000-0000-0000-000000000000"
+#define SLEN(str) (sizeof(str) - 1)
+
+
+int
+posix_handle_relpath (xlator_t *this, uuid_t gfid, const char *basename,
+ char *buf, size_t buflen)
+{
+ char *uuid_str = NULL;
+ int len = 0;
+
+ len = SLEN("../")
+ + SLEN("../")
+ + SLEN("00/")
+ + SLEN("00/")
+ + SLEN(UUID0_STR)
+ + 1 /* '\0' */
+ ;
+
+ if (basename) {
+ len += (strlen (basename) + 1);
+ }
+
+ if (buflen < len || !buf)
+ return len;
+
+ uuid_str = uuid_utoa (gfid);
+
+ if (basename) {
+ len = snprintf (buf, buflen, "../../%02x/%02x/%s/%s",
+ gfid[0], gfid[1], uuid_str, basename);
+ } else {
+ len = snprintf (buf, buflen, "../../%02x/%02x/%s",
+ gfid[0], gfid[1], uuid_str);
+ }
+
+ return len;
+}
+
+
+/*
+ TODO: explain how this pump fixes ELOOP
+*/
+int
+posix_handle_pump (xlator_t *this, char *buf, int len, int maxlen,
+ char *base_str, int base_len, int pfx_len)
+{
+ char linkname[512] = {0,}; /* "../../<gfid>/<NAME_MAX>" */
+ int ret = 0;
+ int blen = 0;
+ int link_len = 0;
+
+ /* is a directory's symlink-handle */
+ ret = readlink (base_str, linkname, 512);
+ if (ret == -1) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "internal readlink failed on %s (%s)",
+ base_str, strerror (errno));
+ goto err;
+ }
+
+ if (ret < 512)
+ linkname[ret] = 0;
+
+ link_len = ret;
+
+ if ((ret == 8) && memcmp (linkname, "../../..", 8) == 0) {
+ if (strcmp (base_str, buf) == 0) {
+ strncpy (buf + pfx_len, "..", 3);
+ }
+ goto out;
+ }
+
+ if (ret < 50 || ret >= 512) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "malformed internal link %s for %s",
+ linkname, base_str);
+ goto err;
+ }
+
+ if (memcmp (linkname, "../../", 6) != 0) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "malformed internal link %s for %s",
+ linkname, base_str);
+ goto err;
+ }
+
+ if ((linkname[2] != '/') ||
+ (linkname[5] != '/') ||
+ (linkname[8] != '/') ||
+ (linkname[11] != '/') ||
+ (linkname[48] != '/')) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "malformed internal link %s for %s",
+ linkname, base_str);
+ goto err;
+ }
+
+ if ((linkname[20] != '-') ||
+ (linkname[25] != '-') ||
+ (linkname[30] != '-') ||
+ (linkname[35] != '-')) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "malformed internal link %s for %s",
+ linkname, base_str);
+ goto err;
+ }
+
+ blen = link_len - 48;
+ memmove (buf + base_len + blen, buf + base_len,
+ (strlen (buf) - base_len) + 1);
+
+ strncpy (base_str + pfx_len, linkname + 6, 42);
+
+ if (len + blen < maxlen)
+ strncpy (buf + pfx_len, linkname + 6, link_len - 6);
+out:
+ return len + blen;
+err:
+ return -1;
+}
+
+
+/*
+ posix_handle_path differs from posix_handle_gfid_path in the way that the
+ path filled in @buf by posix_handle_path will return type IA_IFDIR when
+ an lstat() is performed on it, whereas posix_handle_gfid_path returns path
+ to the handle symlink (typically used for the purpose of unlinking it).
+
+ posix_handle_path also guarantees immunity to ELOOP on the path returned by it
+*/
+
+int
+posix_handle_path (xlator_t *this, uuid_t gfid, const char *basename,
+ char *ubuf, size_t size)
+{
+ struct posix_private *priv = NULL;
+ char *uuid_str = NULL;
+ int len = 0;
+ int ret = -1;
+ struct stat stat;
+ char *base_str = NULL;
+ int base_len = 0;
+ int pfx_len;
+ int maxlen;
+ char *buf;
+
+ priv = this->private;
+
+ uuid_str = uuid_utoa (gfid);
+
+ if (ubuf) {
+ buf = ubuf;
+ maxlen = size;
+ } else {
+ maxlen = PATH_MAX;
+ buf = alloca (maxlen);
+ }
+
+ base_len = (priv->base_path_length + SLEN(HANDLE_PFX) + 45);
+ base_str = alloca (base_len + 1);
+ base_len = snprintf (base_str, base_len + 1, "%s/%s/%02x/%02x/%s",
+ priv->base_path, HANDLE_PFX, gfid[0], gfid[1],
+ uuid_str);
+
+ pfx_len = priv->base_path_length + 1 + SLEN(HANDLE_PFX) + 1;
+
+ if (basename) {
+ len = snprintf (buf, maxlen, "%s/%s", base_str, basename);
+ } else {
+ len = snprintf (buf, maxlen, "%s", base_str);
+ }
+
+ ret = lstat (base_str, &stat);
+
+ if (!(ret == 0 && S_ISLNK(stat.st_mode) && stat.st_nlink == 1))
+ goto out;
+
+ do {
+ errno = 0;
+ ret = posix_handle_pump (this, buf, len, maxlen,
+ base_str, base_len, pfx_len);
+ if (ret == -1)
+ break;
+
+ len = ret;
+
+ ret = lstat (buf, &stat);
+ } while ((ret == -1) && errno == ELOOP);
+
+out:
+ return len + 1;
+}
+
+
+int
+posix_handle_gfid_path (xlator_t *this, uuid_t gfid, const char *basename,
+ char *buf, size_t buflen)
+{
+ struct posix_private *priv = NULL;
+ char *uuid_str = NULL;
+ int len = 0;
+
+ priv = this->private;
+
+ len = priv->base_path_length /* option directory "/export" */
+ + SLEN("/")
+ + SLEN(HANDLE_PFX)
+ + SLEN("/")
+ + SLEN("00/")
+ + SLEN("00/")
+ + SLEN(UUID0_STR)
+ + 1 /* '\0' */
+ ;
+
+ if (basename) {
+ len += (strlen (basename) + 1);
+ } else {
+ len += 256; /* worst-case for directory's symlink-handle expansion */
+ }
+
+ if ((buflen < len) || !buf)
+ return len;
+
+ uuid_str = uuid_utoa (gfid);
+
+ if (__is_root_gfid (gfid)) {
+ if (basename) {
+ len = snprintf (buf, buflen, "%s/%s", priv->base_path,
+ basename);
+ } else {
+ strncpy (buf, priv->base_path, buflen);
+ }
+ goto out;
+ }
+
+ if (basename) {
+ len = snprintf (buf, buflen, "%s/%s/%02x/%02x/%s/%s", priv->base_path,
+ HANDLE_PFX, gfid[0], gfid[1], uuid_str, basename);
+ } else {
+ len = snprintf (buf, buflen, "%s/%s/%02x/%02x/%s", priv->base_path,
+ HANDLE_PFX, gfid[0], gfid[1], uuid_str);
+ }
+out:
+ return len;
+}
+
+
+int
+posix_handle_init (xlator_t *this)
+{
+ struct posix_private *priv = NULL;
+ char *handle_pfx = NULL;
+ int ret = 0;
+ int len = 0;
+ struct stat stbuf;
+ struct stat rootbuf;
+ struct stat exportbuf;
+ char *rootstr = NULL;
+ uuid_t gfid = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
+
+ priv = this->private;
+
+ ret = stat (priv->base_path, &exportbuf);
+ if (ret || !S_ISDIR (exportbuf.st_mode)) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "Not a directory: %s", priv->base_path);
+ return -1;
+ }
+
+ handle_pfx = alloca (priv->base_path_length + 1 + strlen (HANDLE_PFX)
+ + 1);
+
+ sprintf (handle_pfx, "%s/%s", priv->base_path, HANDLE_PFX);
+
+ ret = stat (handle_pfx, &stbuf);
+ switch (ret) {
+ case -1:
+ if (errno == ENOENT) {
+ ret = mkdir (handle_pfx, 0600);
+ if (ret != 0) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "Creating directory %s failed: %s",
+ handle_pfx, strerror (errno));
+ return -1;
+ }
+ } else {
+ gf_log (this->name, GF_LOG_ERROR,
+ "Checking for %s failed: %s",
+ handle_pfx, strerror (errno));
+ return -1;
+ }
+ break;
+ case 0:
+ if (!S_ISDIR (stbuf.st_mode)) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "Not a directory: %s",
+ handle_pfx);
+ return -1;
+ }
+ break;
+ default:
+ break;
+ }
+
+ stat (handle_pfx, &priv->handledir);
+
+ len = posix_handle_path (this, gfid, NULL, NULL, 0);
+ rootstr = alloca (len);
+ posix_handle_path (this, gfid, NULL, rootstr, len);
+
+ ret = stat (rootstr, &rootbuf);
+ switch (ret) {
+ case -1:
+ if (errno != ENOENT) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "%s: %s", priv->base_path,
+ strerror (errno));
+ return -1;
+ }
+
+ ret = posix_handle_mkdir_hashes (this, rootstr);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "mkdir %s failed (%s)",
+ rootstr, strerror (errno));
+ return -1;
+ }
+
+ ret = symlink ("../../..", rootstr);
+ if (ret) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "symlink %s creation failed (%s)",
+ rootstr, strerror (errno));
+ return -1;
+ }
+ break;
+ case 0:
+ if ((exportbuf.st_ino == rootbuf.st_ino) &&
+ (exportbuf.st_dev == rootbuf.st_dev))
+ return 0;
+
+ gf_log (this->name, GF_LOG_ERROR,
+ "Different dirs %s (%lld/%lld) != %s (%lld/%lld)",
+ priv->base_path, (long long) exportbuf.st_ino,
+ (long long) exportbuf.st_dev, rootstr,
+ (long long) rootbuf.st_ino, (long long) rootbuf.st_dev);
+ return -1;
+
+ break;
+ }
+
+ return 0;
+}
+
+
+int
+posix_handle_mkdir_hashes (xlator_t *this, const char *newpath)
+{
+ char *duppath = NULL;
+ char *parpath = NULL;
+ int ret = 0;
+
+ duppath = strdupa (newpath);
+ parpath = dirname (duppath);
+ parpath = dirname (duppath);
+
+ ret = mkdir (parpath, 0700);
+ if (ret == -1 && errno != EEXIST) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "error mkdir hash-1 %s (%s)",
+ parpath, strerror (errno));
+ return -1;
+ }
+
+ strcpy (duppath, newpath);
+ parpath = dirname (duppath);
+
+ ret = mkdir (parpath, 0700);
+ if (ret == -1 && errno != EEXIST) {
+ gf_log (this->name, GF_LOG_ERROR,
+ "error mkdir hash-2 %s (%s)",
+ parpath, strerror (errno));
+ return -1;
+ }
+
+ return 0;
+}
+
+
+int
+posix_handle_hard (xlator_t *this, const char *oldpath, uuid_t gfid, struct stat *oldbuf)
+{
+ char *newpath = NULL;
+ struct stat newbuf;
+ int ret = -1;
+
+
+ MAKE_HANDLE_PATH (newpath, this, gfid, NULL);
+
+ ret = lstat (newpath, &newbuf);
+ if (ret == -1 && errno != ENOENT) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "%s: %s", newpath, strerror (errno));
+ return -1;
+ }
+
+ if (ret == -1 && errno == ENOENT) {
+ ret = posix_handle_mkdir_hashes (this, newpath);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "mkdir %s failed (%s)",
+ newpath, strerror (errno));
+ return -1;
+ }
+
+ ret = link (oldpath, newpath);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "link %s -> %s failed (%s)",
+ oldpath, newpath, strerror (errno));
+ return -1;
+ }
+
+ ret = lstat (newpath, &newbuf);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "lstat on %s failed (%s)",
+ newpath, strerror (errno));
+ return -1;
+ }
+ }
+
+ ret = lstat (newpath, &newbuf);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "lstat on %s failed (%s)", newpath, strerror (errno));
+ return -1;
+ }
+
+ if (newbuf.st_ino != oldbuf->st_ino ||
+ newbuf.st_dev != oldbuf->st_dev) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "mismatching ino/dev between file %s (%lld/%lld) "
+ "and handle %s (%lld/%lld)",
+ oldpath, (long long) oldbuf->st_ino, (long long) oldbuf->st_dev,
+ newpath, (long long) newbuf.st_ino, (long long) newbuf.st_dev);
+ ret = -1;
+ }
+
+ return ret;
+}
+
+
+int
+posix_handle_soft (xlator_t *this, const char *real_path, loc_t *loc,
+ uuid_t gfid, struct stat *oldbuf)
+{
+ char *oldpath = NULL;
+ char *newpath = NULL;
+ struct stat newbuf;
+ int ret = -1;
+
+
+ MAKE_HANDLE_PATH (newpath, this, gfid, NULL);
+ MAKE_HANDLE_RELPATH (oldpath, this, loc->pargfid, loc->name);
+
+
+ ret = lstat (newpath, &newbuf);
+ if (ret == -1 && errno != ENOENT) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "%s: %s", newpath, strerror (errno));
+ return -1;
+ }
+
+ if (ret == -1 && errno == ENOENT) {
+ ret = posix_handle_mkdir_hashes (this, newpath);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "mkdir %s failed (%s)",
+ newpath, strerror (errno));
+ return -1;
+ }
+
+ ret = symlink (oldpath, newpath);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "symlink %s -> %s failed (%s)",
+ oldpath, newpath, strerror (errno));
+ return -1;
+ }
+
+ ret = lstat (newpath, &newbuf);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "stat on %s failed (%s)",
+ newpath, strerror (errno));
+ return -1;
+ }
+ }
+
+ ret = stat (real_path, &newbuf);
+ if (ret) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "stat on %s failed (%s)", newpath, strerror (errno));
+ return -1;
+ }
+
+ if (!oldbuf)
+ return ret;
+
+ if (newbuf.st_ino != oldbuf->st_ino ||
+ newbuf.st_dev != oldbuf->st_dev) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "mismatching ino/dev between file %s (%lld/%lld) "
+ "and handle %s (%lld/%lld)",
+ oldpath, (long long) oldbuf->st_ino, (long long) oldbuf->st_dev,
+ newpath, (long long) newbuf.st_ino, (long long) newbuf.st_dev);
+ ret = -1;
+ }
+
+ return ret;
+}
+
+
+static int
+posix_handle_unset_gfid (xlator_t *this, uuid_t gfid)
+{
+ char *path = NULL;
+ int ret = 0;
+ struct stat stat;
+
+ MAKE_HANDLE_GFID_PATH (path, this, gfid, NULL);
+
+ ret = lstat (path, &stat);
+
+ if (ret == -1) {
+ if (errno != ENOENT) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "%s: %s", path, strerror (errno));
+ }
+ goto out;
+ }
+
+ ret = unlink (path);
+ if (ret == -1) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "unlink %s failed (%s)", path, strerror (errno));
+ }
+
+out:
+ return ret;
+}
+
+
+int
+posix_handle_unset (xlator_t *this, uuid_t gfid, const char *basename)
+{
+ int ret;
+ struct iatt stat;
+ char *path = NULL;
+
+
+ if (!basename) {
+ ret = posix_handle_unset_gfid (this, gfid);
+ return ret;
+ }
+
+ MAKE_HANDLE_PATH (path, this, gfid, basename);
+
+ ret = posix_istat (this, gfid, basename, &stat);
+
+ if (ret == -1) {
+ gf_log (this->name, GF_LOG_WARNING,
+ "%s: %s", path, strerror (errno));
+ return -1;
+ }
+
+ ret = posix_handle_unset_gfid (this, stat.ia_gfid);
+
+ return ret;
+}
+